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The karyotype of the tamaraw was studied using RBG-banding methods and compared with those of the river and swamp cytotypes of domestic water buffalo. The tamaraw karyotype comprises six submetacentric and 16 acrocentric autosome pairs and X and Y chromosome. Chromosome 2 of the tamaraw had larger hybridization signals for the buffalo satellite 1 DNA, and it may have occurred due to relatively recent centromeric fusion.

The genomic DNA of the grasshopper (Oxya hyla intricata) was subjected to electrophoresis after digestion with HaeIII, and the result showed two bands of highly repetitive DNA, approximately 200 and 400 bp in length. The 200-bp HaeIII-digested fragment was cloned and characterized by sequencing and fluorescence in situ hybridization (FISH). The results showed the presence of two distinct satellite DNA (stDNA) families: one consisting of a 169-bp repeated element having an A+T content of 60.9% and the other consisting of a 204-bp repeated element having an A+T content of 53.9%. No significant homology between the two stDNA families was observed. FISH showed that the chromosomal locations of these families are different from each other. The 169-bp element was located in the C-band-positive regions of the short arms of most of the chromosomes, whereas the 204-bp element was located in the centromeric regions of three chromosome pairs. These results imply that the origins of these two DNA families are different. The results of zoo-blot hybridization to the genomic DNA from four Oxya species, O. hyla intricata, O. japonica japonica, O. chinensis formosana, and O. yezoensis, suggest that the two stDNA families found in the present study are species-specific for O. hyla intricata. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The DNA of Apodemus argenteus was digested with Dra I,and the resultant Dra I fragment of highly repetitive DNA was isolated and analyzed by DNA filter hybridization, cloning,sequencing,and fluorescence in situ hybridization (FISH).Southern blot hybridization and nucleotide sequencing revealed that most of the Dra I fragment consisted of a 230-bp repeating unit and contained no sex-chromosome-specific nu- cleotide sequences.The Dra I fragment included the CENP-B box-like sequence,with a strong homology to the human CENP-B box sequence.FISH revealed that the Dra I fragment was specific to all pericentromeric C-band-positive regions,as well as to the C-block of the X chromosome.No hybridization signals were obtained from A.speciosus ,A.peninsulae peninsu- lae ,A.p.giliacus ,A.agrarius ,A.sylvaticus ,A.semotus,or Mus musculus when the Dra I fragment was used as probe.Peptide nucleic acid (PNA)-FISH using the CENP-B box-like sequence in the Dra I fragments as probe suggested that this nucleotide sequence was also specific to all pericentromeric C-heterochro- matic regions of A.argenteus chromosomes .Zoo-blot hybridi- zation using Dra I-digested genomic DNA from three species of Apodemus (namely,A.argenteus ,A.speciosus,and A.peninsu- lae )and from Mus musculus strongly suggested that the consen- sus Dra I fragment contained nucleotide sequences that were species-specific for A.argenteus .These results also suggest that A.argenteus is phylogenetically distant from other Apodemus species examined,as well as the possibility that the Dra I frag- ment might be related directly to the delayed quinacrine mus- tard fluorescence of many pericentromeric C-heterochromatic regions of the chromosomes in A.argenteus . [ABSTRACT FROM AUTHOR]

We have prepared monoclonal antibodies specific for either atrial or ventricular myosin and defined the isomyosin composition of myocardium in normal and overloaded human hearts. In the atrial myocardium, normal isozymic pattern was V1 dominant which converted to being V3 dominant in an overloaded condition. In contrast, normal isomyosin pattern of the ventricular myocardium was exclusively V3 dominant, and only a small change in the proportion of isomyosin was observed in an overloaded condition. From this, we conclude that isozymic changes in cardiac myosin could occur in the human heart to meet increased work induced by cardiac overload. However, the physiological importance of these isomyosin redistributions in human myocardium seems to be much greater in the atrium than in the ventricle, since larger amounts of V1 isomyosin which could be transformed to V3 isomyosin were present in the atrial myocardium. [ABSTRACT FROM PUBLISHER]